Dear colleagues,
We are pleased to share our new open-access publication;
Investigating microplastic trophic transfer in marine top predators
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https://www.sciencedirect.com/science/article/pii/S0269749117343294
Sarah E. Nelms, Tamara S. Galloway, Brendan J. Godley, Dan S. Jarvis, Penelope K. Lindeque
Abstract
Microplastics are highly bioavailable to marine organisms, either through direct ingestion, or indirectly by trophic transfer from contaminated prey. The latter has been observed for low-trophic level organisms in laboratory conditions,
yet empirical evidence in high trophic-level taxa is lacking. In natura studies face difficulties when dealing with contamination and differentiating between directly and indirectly ingested microplastics. The ethical constraints of subjecting large
organisms, such as marine mammals, to laboratory investigations hinder the resolution of these limitations. Here, these issues were resolved by analysing sub-samples of scat from captive grey seals (Halichoerus grypus) and whole digestive tracts of
the wild-caught Atlantic mackerel (Scomber scombrus) they are fed upon. An enzymatic digestion protocol was employed to remove excess organic material and facilitate visual detection of synthetic particles without damaging them. Polymer type was confirmed
using Fourier-Transform Infrared (FTIR) spectroscopy. Extensive contamination control measures were implemented throughout. Approximately half of scat subsamples (48%; n = 15) and a third of fish (32%; n = 10) contained 1–4 microplastics. Particles were mainly
black, clear, red and blue in colour. Mean lengths were 1.5 mm and 2 mm in scats and fish respectively. Ethylene propylene was the most frequently detected polymer type in both. Our findings suggest trophic transfer represents an indirect, yet potentially
major, pathway of microplastic ingestion for any species whose feeding ecology involves the consumption of whole prey, including humans.
Best wishes
Sarah
Sarah Nelms
PhD Researcher
Plymouth Marine Laboratory
Prospect Place, The Hoe, Plymouth. PL1 3DH, UK.
01752 633 416
University of Exeter
Biosciences
http://biosciences.exeter.ac.uk/staff/postgradresearch/index.php?web_id=S_Nelms
Twitter: @SarahENelms